Samples of tissue and bodily fluids are frequently taken from patients for analysis to help in diagnosing disease or monitoring the progress of treatment. Samples may be obtained from a cytological brush, which obtains cells from a mucosal surface using bristles. Aspirates may be obtained from superficial or internal lesions by suction through a fine needle or forceps. Core samples may be obtained from sub mural, sub mucosal, smooth muscle and related tissues adjacent to these cavities. Diagnostic molecular images may be obtained from tissues using optical imaging techniques, such as confocal laser microscopy. Various instruments and methods have been employed to perform these procedures, which are generally well known in the art.
Often, the cytology brush is literally a brush containing bristles that is rubbed on the outer surface of tissues. The bristles are mounted on a wire and may be combined with a needle tip. Typical complications result from kinking of the brush wire, brush hardness and thickness of the bristles.
Needles and forceps are used to sever tissue from the body. For example, biopsies are taken with a needle device that penetrates the tissue and then severs a sample with a sharp cutting cannula. A biopsy forceps having a jaw-type cutter at its end is another example.
An instrument that is commonly used in various types of medical procedures is an inflatable balloon catheter, of which many different types exist, which are utilized to perform various necessary functions. For example, these inflatable balloons are often used to control or stop bleeding, to hold instruments in place, or to prevent or facilitate other flow or movement within the bodily cavity. For example, many urological catheters are held in place via a balloon that impacts the sidewalls of the urinary tract, many gynecological instruments are held in place via balloons that impact the sidewalls of the vaginal vault, endovascular balloons are often used to control bleeding, inflatable balloons are sometimes used to control the backflow of radio-opaque agents injected into the cystic duct to detect the presence of gall stones during general surgical cholecystectomy procedures, and, recently, balloon catheters have been employed to release sinus congestion.
One particular application of such catheters is lung cancer. Among all types of cancer, this has the lowest survival rate, as more than one third of all deaths due to cancer are caused by lung cancer. In the treatment and diagnosis of lung cancer, it is necessary to obtain various biological samples from the lung.
Several devices have been proposed to collect biological samples in internal cavities, and particularly, the lung. For example, U.S. Pat. No. 5,919,145 (Sahatjian) discloses a balloon catheter having a balloon with a porous, hydrogel polymer that swells when exposed to body fluids/tissues, and thus, collects bodily samples. The balloon can be expanded and contracted to create a suction force that pulls sample into the polymer. The goal is to avoid mechanically disturbing the vessel to avoid causing injury.
U.S. Pat. No. 6,398,775 (Perkins et al.) discloses a balloon catheter for isolating a target lung segment and collecting aspirates and/or delivering drug to the isolated segment. Similarly, U.S. Pat. No. 6,527,761 (Soltesz et al.) discloses a catheter for collecting aspirates. An anchor, which may be a balloon, is used to anchor the catheter for aspiration.
Further, U.S. Pat. Nos. 7,670,282 and 7,775,968 (Mathis) disclose a balloon catheter for delivery of a biopsy needle. The balloon is used to move the needle towards to the biopsy site. Alternatively, a cutter tool may be used to collect sample.
While the above described systems are useful for collecting samples within a patient's body, these systems still suffer from a number of disadvantages and drawbacks. One of the major problems with the prior art systems described above is that multiple types of samples cannot be collected at the same time or with the same catheter. Additionally, these known systems are typically constructed with expensive materials and require multiple working components, and therefore, have to be reused multiple times, which requires complex sterilization procedures.
A further deficiency of the prior art systems described above is that they are not capable of being positioned as optimally and precisely as may be desired. The known devices do not provide illumination and a direct visual feedback of the area ahead, behind, and around the device to optimize positioning and operation of the device.
In light of the prevalence and seriousness of pulmonary diseases, such as lung cancer, there is a need to obtain cell and tissue samples from the respiratory tract. In particular, there is a need to obtain biopsies, aspirates and cytological specimens in the target junctions of bronchial airways in an efficient and cost-effective manner.
What is desired, therefore, is an improved system and method for collecting biological samples at specific locations inside a patient's body that addresses the disadvantages and shortcomings of the prior art systems described above.